Personnel door for air supported tents



Sept. 7, 1965 F. o. JOHNSON 3,204,649

PERSONNEL DOOR FOR AIR SUPPORTED TENTS Filed Aug. 9, 1963 5 Fan/f 0 Johnson I I 4 )V U! J'- (1 31% ZMM W K ,0 A? W ATTORNEYS.

United States Patent 3,204,649 PERSONNEL DOOR FOR AIR SUPPORTED TENTS Frank 0. Johnson, Leicester, Mass, assignor to the United States of America as represented by the Secretary of the Army Filed Aug. 9, 1963, Ser. No. 301,218 4 Claims. ('Cl. 1351'4) (Granted under Title 35, U.S. Code (1952), sec. 266) The invention described herein, if patented, may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

The invention relates to tents of the frameless type which are formed of lightweight and substantially impervious material. The lower edges of the walls of such tents are sealed to the ground and the rest of the tent is supported above the ground by low air pressure. In such tents it is a problem to provide access to the interior without undue loss of air pressure. Ordinary tent doors are, of course, insufficiently air tight for this purpose and the currently used double door vestibule type of entry is cumbersome, expensive and difficult to set up.

With the foregoing in view, it is an object of the invention to provide an improved closure and access opening combination for a tent of this type.

A further object is to provide such a combination wherein the closure is secured in the closed position in sealing relation to the access opening by the pressure of air which supports the tent.

A further object is to provide in such a combination novel means wherein the closure is automatically maintained in the closed position by gravity.

Other objects and advantages reside in the specific structure of the invention, the structure of the several elements of the same, combinations and subcombinations of such elements with each other and/or with the tent, all of which will be readily apparent to those skilled in the art upon reference to the attached drawing which illustrates one species of the invention and to the following specification wherein the invention is described and claimed.

In the drawing:

FIGURE 1 is a fragmentary rear elevational view of the inside of a tent wall showing a closure according to the invention in place across an access opening in the wall;

FIGURE 2 is a view like FIGURE 1 but taken from outside the tent;

FIGURE 3 is an enlarged fragmentary horizontal sectional view taken substantially on the plane of the line 3--3 of FIGURE 1; and

FIGURE 4 is a similar sectional view but taken substantially on the plane of the line 44 of FIGURE 2.

Referring specifically to the drawing wherein like reference characters indicate like parts in all views, designates a wall for an air supported tent which may be formed from any suitable lightweight and substantially impervious material. An access opening is formed through the wall. Such opening may be of various shapes but is preferably circular. An annulus 11 of suitable semi-rigid material such as metal cable is secured in a hem 12 to define the access opening and to provide a head the purpose of which will be apparent later. The ends of the cable 11 may be secured together by any suitable means such as the clip 13, FIGURE 2.

The closure 14 comprises a disc of any suitable lightweight and substantially impervious material. Preferably, the closure 14 is made of the same material as the tent wall by any suitable first hinge means. Such hinge A hoop 15 of suitable metallic material such as stainless "ice steel is secured in a hem 16 of the closure. An annular portion of the hem 16 is formed to provide a welt 17 which is slightly compressible to provide a sealing gasket between the hoop and the tent wall 10, radially outwardly of the access opening.

The closure 14 is provided with any suitable handgrip 18 on the inside thereof. On the side of the closure 14 opposite to the handgrip, the closure is hinged to the tent wall by any suitable first hinge means. Such hinge means as shown comprises a short length of light rope 19 which extends through aligned grommets 20, 21 secured respectively in tent wall 10 and closure 14. The rope 19 may be doubled about a toggle 22, FIGURE 4, on the inside of the tent with the ends knotted together as at 23 outside the closure 14. A reinforcing patch 24 may be secured to the tent wall 10 at this point if desirable.

The rope hinge 19 is supplemented by a second hinge means 25 which comprises a length of light rope or line 26 which is doubled and which has the bight 27 thereof secured to the tent wall in any suitable manner in upwardly spaced relation to the closure centrally thereof. The lower ends of the line 26 are spread apart and secured to the top of the closure 14 in any suitable manner as by being knotted to reinforcing patches 28 stitched to the closure 14. As is readily apparent from FIG- URE 1, the axis of the hinge for the closure 14 is a diagonal line which extends from the first hinge means 1% to the bight 27 of the upper hinge means 25. The etiect of this structure is to load the closure 14 to the closed position by the force of gravity. The resilience of the hoop 15 permits slight bending of the closure 14 and enhances the force of gravity to snap the closure shut from the open position when it is released. Once closed, the closure 14 is held in sealing relation to the opening by the pressure of the air which supports the tent. Also, the air pressure will force a concentric circular inner portion of the closure 14 into tight engagement with the bead formed by the cable 11 and which defines the opening in the tent. Thus, in effect, the structure provides a double seal for the access opening.

It is apparent that the structure shown and described is one which is readily manufactured of low cost materials and one which closes quickly and automatically when released and which can be used as a single door or as the inner door in the vestibule type of entrance. Also, although there has been shown and described what is now thought to be the preferred embodiment of the invention, still it should understood that the same is susceptible of other forms and expressions. Consequently, the invention is not considered as being limited to the exact structure shown and described hereinabove but only as hereinafter claimed.

I claim:

1. The combination with an air supported tent of light weight and substantially impervious wall material, said material having an access opening formed therethrough, there being reinforcing frame means extending entirely around said opening; of a closure for said opening, said closure being formed of lightweight impervious material, said closure being larger than said opening and overlapping the same in all directions on the inside of the tent, a reinforcing hoop secured to the outer edges of said closure adapted to overlie said reinforcing frame means, hinge means on one side of said closure securing same to the tent for swinging movement to and from open and closed positions, a second hinge means comprising at least one strand secured at one end to the upper portion of said closure and at the other end to the tent at a point substantially above said closure, said first and second hinge means cooperating to permit said closure to be opened diagonally upwardly and to be closed by gravity,

sealing means carried by said closure providing an air seal between said closure and opening, and said closure being adapted to be secured in sealing relation to said opening by air pressure inside said tent.

2. The combination of claim 1, wherein said closure and opening are circular in shape and wherein said hoop is of resilient metallic material.

3. An air supported tent having an access opening therethrough with a rigid reinforcing frame member surrounding the opening, the improvement of a closure for said opening comprising a flap of a size and configuration to overlie said opening and said frame member, a reinforcing hoop secured to the outer edges of said flap adapted to overlie said frame member, hinge means on one side of said closure securing same to the tent for swinging movement to and from open and closed positions, a second hinge means comprising at least one strand secured at one end to the upper portion of said closure and at the other end to the tent at a point substantially above said closure, said first and second hinge means cooperating to permit said closure to be opened diagonally up- 4 wardly and to be closed by gravity, and fastening means securing said closure to said tent in diagonally downwardly spaced relation to said second mentioned hinge means.

4. The structure of claim 3, wherein said closure is provided with a hem enclosing said hoop, and a welt provided by said hem bearing against said hoop and said tent to form a seal.

References Cited by the Examiner UNITED STATES PATENTS 3,000,376 9/61 Smith et a1. 128-1.02 3,059,655 10/62 Bird 1351 3,075,254 1/63 Jacobson et a1. 2016 3,085,297 4/63 Linderfelt 2016 FOREIGN PATENTS 448,129 6/36 Great Britain. 155,790 8/56 Sweden.

20 HARRISON R. MOSELEY, Primary Examiner. 

3. AN AIR SUPPORTED TENT HAVING AN ACCESS OPENING THERETHROUGH WITH A RIGID REINFORCING FRAME MEMBER SURROUNDING THE OPENING, THE IMPROVEMENT OF A CLOSURE FOR SAID OPENING COMPRISING A FLAP OF SIZE AND CONFIGURATION TO OVERLIE SAID OPENING AND SAID FRAME MEMBER, A REINFORCING HOOP SECURED TO THE OUTER EDGES OF SAID FLAP ADAPTED TO OVERLIE SAID FRAME MEMBER, HINGE MEANS ON ONE SIDE OF SAID CLOSURE SECURING SAME TO THE TENT FOR SWINGING MOVEMENT TO AND FROM OPEN AND CLOSED POSITIONS, A SECOND HINGE MEANS COMPRISING AT LEAST ONE STRAND SECURED AT ONE END TO THE UPPER PORTION OF SAID CLOSURE AND AT THE OTHER END TO THE TENT AT A POINT SUBSTANTIALLY ABOVE SAID CLOSURE, SAID FIRST AND SECOND HINGE MEANS COOPERAT- 